Dogs, drones and sound detectors: How rescuers search for quake survivors

Specially-trained search dogs are used to sniff out where potential victims may be located, says Ivory - who has been deployed to relief efforts following earthquakes in Haiti, Japan and Nepal and is currently helping to coordinate efforts in Venezuela from the UK. They can identify a person's smell even when they are buried as far as 10m (32.8ft) under rubble - and will let out a "really strong and sustained bark" when they do, alerting rescuers to a potential survivor. The dogs are trained using toys imprinted with a human's smell, Ivory explains. Then, when they actually locate a human on the ground, they are handed the toy as a reward by their handler. Search dogs can also be very useful during the technical part of rescue operations, says Sakthy Selvakumaran of the UK-based charity Search and Rescue Assistance in Disasters (SARAID), which deploys personnel to large-scale disasters worldwide. They can find hard-to-navigate paths through rubble to follow a scent or identify different access points to the victim, Selvakumaran tells the BBC.